Bryde's whales hid for decades inside whalers' sei whale catches
Japanese whalers now call it the look-alike whale. For years, animals landed off Japan and Brazil as sei whales turned out to be a different species entirely, betrayed by three ridges on the snout instead of one. Even today scientists cannot agree how many species the Bryde's whale group actually contains.
Researchers speak of a Bryde's whale complex: probably three species, perhaps four. The common Bryde's whale roams warm seas worldwide, while the smaller Eden's whale may live only in the Indo-Pacific. Two former members have already been split off, Omura's whale in 2003 and Rice's whale of the Gulf of Mexico in 2021. The name honours Johan Bryde, a Norwegian consul who helped found South Africa's first modern whaling station.
The confusion goes back well over a century. Eden's whale was described in 1878 from an 11-metre animal that had stranded in 1871 after swimming more than 32 kilometres up a creek in Burma. In 1913 a Norwegian scientist named the common species from a dozen supposed sei whales at South African stations, and in 1950 a Dutch researcher lumped the two back together. Only in the 1950s did Japanese studies show that southern sei whales had coarser baleen, longer throat grooves and a differently shaped palate, and in the 1960s the same traits exposed Bryde's whales among Brazil's catch.
These are slim, smoky grey rorquals, related to blue and humpback whales, usually 12 to 25 tonnes and up to about 15 metres long. They are even more elongated than fin whales. They surface at unpredictable intervals, change direction for no obvious reason, sometimes exhale underwater, and produce short, low moans. Dives normally last five to fifteen minutes and can reach 292 metres.
Diet depends on where they live. Off South Africa, coastal whales mostly chase schooling fish, while offshore animals eat krill-like euphausiids and deep-sea fish; one was found packed with baby squid. Near Japan, whales close to shore favour euphausiids in early summer, while those farther out switch almost entirely to anchovy by late summer.
Source: Bryde's whale
